1. Field of the Invention
The present invention relates to a multi-streaming apparatus and a multi-streaming method, and more particularly, to a multi-streaming apparatus and a multi-streaming method which reduce noise and provide a content copy protection by using a temporary storage medium.
2. Description of Related Art
Conventional home networks require multi-streaming of contents stored in a storage medium to a plurality of players. Typically, a streaming apparatus reads contents from a storage medium and produces streaming packets to transmit them to one or more players. The player receives packets, reorganizes the contents, decodes them according to a predetermined moving picture compression standard, and plays back the contents.
A streaming apparatus can read different portions of a certain content stored in a storage medium. For example, two or more players may simultaneously read a 2-hour movie from a 5-minute location after the start of the movie and from a 1-hour location after the start of the movie, respectively. In addition, a streaming server in the player can perform a multi-streaming of the contents from one or more sources.
FIG. 1 illustrates a conventional streaming apparatus 10.
The streaming apparatus 10 includes a disc drive 12, a decryption unit 13, and a streaming server 14.
The disc drive 12 reads binary signals from a storage medium 11, and extracts a content key 16 and key generation information 17 from the binary signals. The key generation information 17 is information used to decrypt the contents, for example, information used to produce the decryption key for decrypting the contents.
The decryption unit 13 decrypts the contents 16 based on the key generation information 17 and additional information to produce decrypted contents 18. Here, the additional information means information used or generated in the streaming apparatus 10. The decryption unit 13 may include all functions necessary for only authorized persons to decrypt corresponding contents through various methods such as authentication of the streaming apparatus. Thus, the decryption unit 13 is called a content protection system (CPS).
The streaming server 14 produces streaming packets 19 by using the decrypted contents 18 and transmits the streaming packets to the player 20.
The player 20 includes a streaming client 21 and a decoder 22. The streaming client 21 combines the streaming packets 19 to reorganize the contents 23, and the decoder 22 decodes the contents 23 according to a predetermined moving picture compression standard to produce video signals 24 and display them.
When two or more players 20 are provided, the disc drive 12, the decryption unit 13, and the streaming server 14 are concurrently operated in the streaming apparatus 10. For convenience of explanation, a stream to a first device is referred to as a first stream and a stream to a second device is referred to as a second stream. The disc drive 12 concurrently reads binary signals corresponding to the first stream and the second stream, respectively, and extracts contents and key generation information of the first stream, and another contents and key generation information of the second stream, respectively. Also, the decryption unit 13 and the streaming server 14 concurrently process a decryption and streaming procedure for the first stream and another decryption and decryption procedure for the second stream.
Unfortunately, the conventional streaming apparatus generates noise. Since the disc drive is required to read the binary signals from a storage medium 11 at a speed of “1× speed*the number of players,” in theory, the disc must be rotated at a high speed, thereby generating noise.
For example, supposing a family member in a living room starts to watch a movie stored in a blue-ray disc ROM installed in the living room, and another family member in another room tries to watch the same movie from the beginning after one hour, the family member in the living room will see the movie with noise caused by the rotation of the disc.
Furthermore, an experimental result shows that the blue-ray disc would require a 4× or more speed for a normal playback in streaming a video content to two or more players when the video content to be played requires a high definition (HD) quality or higher. In this case, the noise problem can not be avoided.
On the other hand, recently, the whole contents are encrypted and then stored in a storage medium for copy protection, and a content protection system is included in a streaming apparatus. However, a multi-streaming apparatus having such a copy protection function has not been yet provided.